Downlink bandwidth transmission method and apparatus for passive optical network

ABSTRACT

A downstream bandwidth transmission method for a passive optical network includes: performing a downstream bandwidth allocation ( 101 ); sending a result of the downstream bandwidth allocation ( 102 ); and sending traffic data based on the result of the downstream bandwidth allocation, where the result of the downstream bandwidth allocation carries optical network unit (ONU) indication information ( 103 ).

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a National Stage Application, filed under 35 U.S.C. 371, ofInternational Patent Application No. PCT/CN2018/113132, filed on Oct.31, 2018, which claims the priority of Chinese patent application No.201711060252.3 filed on Nov. 1, 2017, contents of both of which areincorporated herein by reference in their entireties.

TECHNICAL FIELD

The present disclosure relates to, but is not limited to, the field ofcommunications and, in particular, relates to a downstream bandwidthtransmission method and apparatus for a passive optical network.

BACKGROUND

A traditional passive optical network system has a point-to-multipointnetwork topology. One optical line terminal (OLT) is connected tomultiple optical network units (ONUs) through an optical distributionnetwork (ODN). In a downstream direction, all ONUs will receive datasent by the OLT. Therefore, no matter which ONU is downstream data sentto, every ONU needs to attempt to parse the downstream data, only whenthe parsed downstream data is sent to itself, the ONU receives thedownstream data; and the ONU will discard the downstream data when theparsed downstream data is not sent to itself. In a process of parsingthe downstream data, a frame header may be generally determined,including a frame header detection, an error correction, anidentification determination, etc., which increases complexity, powerconsumption, even costs and so on of the ONU. In addition, when parsingof a certain frame header in the downstream data fails, it may alsocause rest of the downstream data to be lost.

In the passive optical network system, in some cases, the OLT performsbandwidth scheduling in the downstream direction, but does not notifythe ONU of the other party of a result of the bandwidth scheduling whichis only used locally. Using this kind of scheduling manner, on one hand,the OLT adjusts scheduling in real time in a certain manner, whichrequires complex algorithms; on the other hand, the OLT does not notifythe other party of the scheduling result, the ONU needs to parse framesone by one, and each ONU can only perform serial processing, which has alow efficiency and it is inferior to parallel processing of ONUs with ahigh efficiency.

SUMMARY

The present disclosure provides a downstream bandwidth transmissionmethod and apparatus for a passive optical network, so as to improveefficiency and reduce complexity.

Schemes of the embodiments of the present disclosure are implemented asdescribed below.

The present disclosure provides a downstream bandwidth transmissionmethod for a passive optical network. The method includes stepsdescribed below. An OLT performs a downstream bandwidth allocation. TheOLT sends a result of the downstream bandwidth allocation. The OLT sendstraffic data based on the result of the downstream bandwidth allocation.The result of the downstream bandwidth allocation sent by the OLTcarries optical network unit (ONU) indication information.

The present disclosure further provides a downstream bandwidthtransmission apparatus for a passive optical network. The apparatusincludes a processor and a memory configured to store computer programsexecutable on the processor, where the processor is configured to: whenexecuting the computer programs, perform steps of the method describedabove.

The present disclosure further provides a downstream bandwidthtransmission method for a passive optical network. The method includessteps described below. An ONU receives and parses a result of adownstream bandwidth allocation. The ONU receives traffic data in acorresponding slot based on ONU indication information in the result ofdownstream bandwidth allocation. The result of downstream bandwidthallocation carries the optical network unit (ONU) indicationinformation.

The present disclosure further provides a downstream bandwidthtransmission apparatus for a passive optical network. The apparatusincludes a processor and a memory configured to store computer programsexecutable on the processor, where the processor is configured to: whenexecuting the computer programs, perform steps of the method describedabove.

The present disclosure further provides a downstream bandwidthtransmission method for a passive optical network. The method includessteps described below. An OLT performs a downstream bandwidthallocation, sends a result of the downstream bandwidth allocation to anONU, and sends traffic data based on the result of the downstreambandwidth allocation. The ONU receives and parses the result of thedownstream bandwidth allocation, and receives traffic data in acorresponding slot based on ONU indication information in the result ofthe downstream bandwidth allocation. The result of the downstreambandwidth allocation carries the optical network unit (ONU) indicationinformation.

The present disclosure further provides a downstream bandwidthtransmission apparatus for a passive optical network. The apparatusincludes an allocation module and a sending module. The allocationmodule is configured to perform a downstream bandwidth allocation. Thesending module is configured to send a result of the downstreambandwidth allocation and send traffic data based on the result of thedownstream bandwidth allocation. The result of the downstream bandwidthallocation carries optical network unit (ONU) indication information.

The present disclosure further provides a downstream bandwidthtransmission apparatus for a passive optical network. The apparatusincludes a first receiving module and a second receiving module. Thefirst receiving module is configured to receive and parse a result of adownstream bandwidth allocation. The second receiving module isconfigured to receive traffic data in a corresponding slot based on ONUindication information in the result of the downstream bandwidthallocation. The result of downstream bandwidth allocation carries theoptical network unit (ONU) indication information.

The present disclosure further provides a computer-readable storagemedium, which is configured to store computer-executable instructionswhich, when executed, implement the downstream bandwidth transmissionmethod for the passive optical network described above.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a flowchart of a downstream bandwidth transmission method fora passive optical network according to an embodiment of the presentdisclosure;

FIG. 2 is a flowchart of another downstream bandwidth transmissionmethod for a passive optical network according to an embodiment of thepresent disclosure;

FIG. 3 is a structural diagram of a downstream bandwidth transmissionapparatus for a passive optical network according to an embodiment ofthe present disclosure;

FIG. 4 is a structural diagram of an allocation module according to anembodiment of the present disclosure;

FIG. 5 is a structural diagram of a sending module according to anembodiment of the present disclosure;

FIG. 6 is a structural diagram of another downstream bandwidthtransmission apparatus for a passive optical network according to anembodiment of the present disclosure;

FIG. 7 is a structural diagram of a first receiving module according toan embodiment of the present disclosure;

FIG. 8 is a structural diagram of a traditional gigabit passive opticalnetwork (GPON) superframe, a GPON transmission convergence (GTC) frame;

FIG. 9 is a structural diagram of a traditional GPON encapsulationmethod (GEM) frame;

FIG. 10 is a structural diagram of a traditional 10 gigabit passiveoptical network (XG-PON) superframe, an XG-PON transmission convergence(XGTC) frame;

FIG. 11 is a structural diagram of a traditional XGTC payload composedof XG-PON encapsulation method (XGEM) frames;

FIG. 12 is a structural diagram of a downstream bandwidth allocation ina GPON system according to an embodiment of the present disclosure;

FIG. 13 is a diagram illustrating an implementation of a downstreambandwidth allocation in a GPON system according to an embodiment of thepresent disclosure;

FIG. 14 is a schematic diagram of a downstream bandwidth allocation inan XG-PON system according to an embodiment of the present disclosure;

FIG. 15 is a diagram illustrating an implementation of a downstreambandwidth allocation in an XG-PON system according to an embodiment ofthe present disclosure;

FIG. 16 is a structural diagram of a downstream bandwidth allocation(DS_GATE) message according to an embodiment of the present disclosure;and

FIG. 17 is another structural diagram of a DS_GATE message according toan embodiment of the present disclosure.

DETAILED DESCRIPTION

Embodiments of the present disclosure are described hereinafter inconjunction with the drawings.

An embodiment of the present disclosure provides a downstream bandwidthtransmission method for a passive optical network. The method is appliedto an OLT. As shown in FIG. 1, the method may include steps describedbelow. In step 101, the OLT performs a downstream bandwidth allocation.In step 102, the OLT sends a result of the downstream bandwidthallocation. In step 103, the OLT sends traffic data based on the resultof the downstream bandwidth allocation, where the result of thedownstream bandwidth allocation carries optical network unit (ONU)indication information.

In the embodiments of the present disclosure, the ONU indicationinformation may be used for indicating that a downstream bandwidth isallocated to which ONU.

In the embodiments of the present disclosure, the downstream bandwidthis allocated to an ONU, and the corresponding ONU indication informationis sent; after parsing the result of the downstream bandwidthallocation, the ONU receives downstream traffic data within thedownstream bandwidth sent to the ONU itself, unnecessary parsing anddetermination behaviors are avoided, thereby improving systemefficiency, reducing energy consumption, and simplifying systemimplementation complexity.

In the embodiments of the present disclosure, the step in which the OLTperforms the downstream bandwidth allocation may include that the OLTperforms the downstream bandwidth allocation based on a local trafficdata queue.

In the embodiments of the present disclosure, the step in which thedownstream bandwidth allocation is performed based on the local trafficdata queue may include steps described below. One or more local trafficdata queues are established, and a priority is configured for each queueof the one or more local traffic data queues. Based on a downstreambandwidth scheduling algorithm, a downstream bandwidth occupied by eachqueue of the one or more local traffic data queues is determinedaccording to a data length and the priority of each queue of the one ormore local traffic data queues, and the downstream bandwidth allocationis performed.

In an embodiment, after the downstream bandwidth occupied by each queueof the one or more local traffic data queues is determined and thedownstream bandwidth allocation is performed, the method may furtherinclude a step described below. Downstream bandwidths belonging to asame ONU are configured to be consecutive.

In an embodiment, the step of sending the result of the downstreambandwidth allocation may include a step described below. Downstreambandwidth allocation information is carried in a downstream frame, whereeach downstream bandwidth entry in the downstream bandwidth allocationinformation includes the ONU indication information (for example, anONU-ID indicating that the downstream bandwidth is allocated to whichONU, that is, the ONU indication information) and downstream bandwidthfeature information (for example, starting time and ending time of thedownstream bandwidth, the starting time and a bandwidth length of thedownstream bandwidth or the like). Alternatively, an indication messageof the downstream bandwidth allocation (for example, a DS_GATE message)is sent, where the indication message carries the ONU indicationinformation (for example, a logical link identification (LLID), aphysical link identification (PLID) or the like).

An embodiment of the present disclosure further provides a downstreambandwidth transmission method for a passive optical network. As shown inFIG. 2, the method may include steps described below. In step 201, anONU receives and parses a result of a downstream bandwidth allocation.In step 202, the ONU receives traffic data in a corresponding slot basedon ONU indication information in the result of the downstream bandwidthallocation, where the result of downstream bandwidth allocation carriesthe optical network unit (ONU) indication information.

In the embodiments of the present disclosure, a downstream bandwidth isallocated to the ONU, and the corresponding ONU indication informationis sent; and after parsing the result of downstream bandwidthallocation, the ONU receives downstream traffic data within thedownstream bandwidth corresponding to the ONU itself, unnecessaryparsing and determination behaviors are avoided, thereby improvingsystem efficiency, reducing energy consumption, and simplifying systemimplementation complexity.

In the embodiments of the present disclosure, the step of receiving andparsing the result of downstream bandwidth allocation may include stepsdescribed below. Each downstream bandwidth entry is acquired and parsed.And, it is determined whether the ONU indication information in adownstream bandwidth entry is consistent with identification informationof the ONU.

In an embodiment, the step of receiving the traffic data of thecorresponding slot (a slot corresponding to the ONU) based on the resultof the downstream bandwidth allocation may include steps describedbelow. When it is determined that the ONU indication information in thedownstream bandwidth entry is consistent with the identificationinformation of the ONU, the downstream bandwidth feature information inthe downstream bandwidth entry is acquired, and the traffic data in thecorresponding slot is obtained based on the downstream bandwidth featureinformation.

In an embodiment, the step of receiving the traffic data in thecorresponding slot based on the result of the downstream bandwidthallocation may include a step described below. When it is determinedthat the ONU indication information in the downstream bandwidth entry isinconsistent with the identification information of the ONU, nosubsequent processing is performed on the downstream bandwidth entry anda downstream bandwidth corresponding to the downstream bandwidth entry(operations such as acquisition of the downstream bandwidth featureinformation and acquisition of the traffic data are not performed).

An embodiment of the present disclosure further provides a downstreambandwidth transmission method for a passive optical network. The methodmay include steps described below. An OLT performs a downstreambandwidth allocation, sends a result of the downstream bandwidthallocation to an ONU, and sends traffic data based on the result of thedownstream bandwidth allocation. The ONU receives and parses the resultof the downstream bandwidth allocation, and receives traffic data in acorresponding slot based on ONU indication information in the result ofthe downstream bandwidth allocation. Where, the result of the downstreambandwidth allocation carries the optical network unit (ONU) indicationinformation.

An embodiment of the present disclosure further provides a downstreambandwidth transmission apparatus for a passive optical network. As shownin FIG. 3, the apparatus may include an allocation module 301 and asending module 302. The allocation module 301 is configured to perform adownstream bandwidth allocation. The sending module 302 is configured tosend a result of the downstream bandwidth allocation and send trafficdata based on the result of the downstream bandwidth allocation. Theresult of the downstream bandwidth allocation carries optical networkunit (ONU) indication information.

In an embodiment, the allocation module 301 may perform the downstreambandwidth allocation by performing the downstream bandwidth allocationbased on a local traffic data queue.

In an embodiment, as shown in FIG. 4, the allocation module 301 mayinclude a configuration unit 3011 and a processing unit 3012. Theconfiguration unit 3011 is configured to establish one or more localtraffic data queues, and configure a priority for each queue of the oneor more local traffic data queues. The processing unit 3012 isconfigured to: based on a downstream bandwidth scheduling algorithm,determine a downstream bandwidth occupied by each queue of the one ormore local traffic data queues according to a data length and thepriority of each queue of the one or more local traffic data queues, andperform the downstream bandwidth allocation.

In the embodiments of the present disclosure, as shown in FIG. 5, thesending module 302 may include a first sending unit 3021 or a secondsending unit 3022. The first sending unit 3021 is configured to carrydownstream bandwidth allocation information in a downstream superframe,where each downstream bandwidth entry in the downstream bandwidthallocation information includes the ONU indication information anddownstream bandwidth feature information. The second sending unit 3022is configured to send an indication message of the downstream bandwidthallocation, where the indication message carries the ONU indicationinformation.

In an embodiment, the allocation module 301 may be further configured toconfigure downstream bandwidths belonging to a same ONU to beconsecutive.

An embodiment of the present disclosure further provides a downstreambandwidth transmission apparatus for a passive optical network. As shownin FIG. 6, the apparatus may include a first receiving module 601 and asecond receiving module 602. The first receiving module 601 isconfigured to receive and parse a result of a downstream bandwidthallocation. The second receiving module 602 is configured to receivetraffic data in a corresponding slot based on ONU indication informationin the result of the downstream bandwidth allocation, where the resultof the downstream bandwidth allocation carries the optical network unit(ONU) indication information.

In the embodiments of the present disclosure, as shown in FIG. 7, thefirst receiving module 601 may include a parsing unit 6011 and adetermination unit 6012. The parsing unit 6011 is configured to acquireand parse each downstream bandwidth entry. The determination unit 6012is configured to determine whether the ONU indication information in adownstream bandwidth entry is consistent with identification informationof an ONU.

In the embodiments of the present disclosure, the second receivingmodule 602 may receive the traffic data in the corresponding slot basedon the result of the downstream bandwidth allocation in a mannerdescribed below. When it is determined that the ONU indicationinformation in the downstream bandwidth entry is consistent with theidentification information of the ONU, downstream bandwidth featureinformation in the downstream bandwidth entry is acquired, and thetraffic data in the corresponding slot is obtained based on thedownstream bandwidth feature information.

An embodiment of the present disclosure further provides a downstreambandwidth transmission system for a passive optical network. The systemmay include an OLT and one or more ONUs. The OLT is configured to:perform a downstream bandwidth allocation, send a result of thedownstream bandwidth allocation to the one or more ONUs, and sendtraffic data based on the result of the downstream bandwidth allocation.Each of the one or more ONUs is configured to: receive and parse theresult of the downstream bandwidth allocation, and receive traffic datain a corresponding slot based on ONU indication information in theresult of the downstream bandwidth allocation, where the result of thedownstream bandwidth allocation carries the optical network unit (ONU)indication information.

An embodiment of the present disclosure further provides a downstreambandwidth transmission apparatus for a passive optical network. Theapparatus may include a processor and a memory configured to storecomputer programs executable on the processor. The processor isconfigured to: when executing the computer programs, perform adownstream bandwidth allocation, send a result of the downstreambandwidth allocation, and send traffic data based on the result of thedownstream bandwidth allocation. The result of the downstream bandwidthallocation carries optical network unit (ONU) indication information.

When an OLT performs the downstream bandwidth allocation, the processormay be further configured to: when executing the computer programs,perform the downstream bandwidth allocation based on a local trafficdata queue.

When the downstream bandwidth allocation is performed based on the localtraffic data queue, the processor may be further configured to: whenexecuting the computer programs, perform steps described below. One ormore local traffic data queues are established, and a priority isconfigured for each queue of the one or more local traffic data queues.Based on a downstream bandwidth scheduling algorithm, a downstreambandwidth occupied by each queue of the one or more local traffic dataqueues is determined according to a data length and the priority of eachqueue of the one or more local traffic data queues, and the downstreambandwidth allocation is performed.

After the downstream bandwidth occupied by each queue of the one or morelocal traffic data queues is determined and the downstream bandwidthallocation is performed, the processor may be further configured to:when executing the computer programs, configure downstream bandwidthsbelonging to a same ONU to be consecutive.

When the result of the downstream bandwidth allocation is sent, theprocessor may be further configured to: when executing the computerprograms, perform a step described below. Downstream bandwidthallocation information is carried in a downstream frame, where eachdownstream bandwidth entry in the downstream bandwidth allocationinformation includes the ONU indication information and downstreambandwidth feature information. Alternatively, an indication message ofthe downstream bandwidth allocation is sent, where the indicationmessage carries the ONU indication information.

An embodiment of the present disclosure further provides a downstreambandwidth transmission apparatus for a passive optical network. Theapparatus may include a processor and a memory configured to storecomputer programs executable on the processor. The processor isconfigured to: when executing the computer programs, receive and parse aresult of a downstream bandwidth allocation, and receive traffic data ina corresponding slot based on ONU indication information in the resultof downstream bandwidth allocation. The result of downstream bandwidthallocation carries the optical network unit (ONU) indicationinformation.

When the result of downstream bandwidth allocation is received andparsed, the processor may be further configured to: when executing thecomputer programs, perform steps described below. Each downstreambandwidth entry is acquired and parsed. And it is determined whether theONU indication information in the downstream bandwidth entry isconsistent with identification information of an ONU.

When the traffic data in the corresponding slot is received based on theresult of the downstream bandwidth allocation, the processor may befurther configured to: when executing the computer programs, perform astep described below. When it is determined that the ONU indicationinformation in the downstream bandwidth entry is consistent with theidentification information of the ONU, downstream bandwidth featureinformation in the downstream bandwidth entry is acquired, and thetraffic data in the corresponding slot is obtained based on thedownstream bandwidth feature information.

It may be illustrated that when the apparatus according to theabove-mentioned embodiments performs a downstream bandwidthtransmission, an exemplary description is provided merely through thedivision of program modules described above. In practical applications,the processing described above may be assigned to different programmodules to be implemented according to needs, that is, an internalstructure of a device is divided into different program modules toimplement all or part of the processing described above. In addition,the apparatus according to the above-mentioned embodiments has the sameconcept as the corresponding method embodiments, and for animplementation process, reference is made to the method embodiments andrepetition is not made herein.

In an exemplary embodiment, the embodiment of the present disclosurefurther provides a computer-readable storage medium. Thecomputer-readable storage medium may be a ferroelectric random accessmemory (FRAM), a read-only memory (ROM), a programmable read-only memory(PROM), an electrically programmable read-only memory (EPROM), anelectrically erasable programmable read-only memory (EEPROM), a flashmemory, a magnetic surface memory, an optical disk, a compact discread-only memory (CD-ROM) or other memories, or may be any deviceincluding one or any combination of the memories described above, suchas a mobile phone, a computer, a tablet device or a personal digitalassistant.

An embodiment of the present disclosure further provides acomputer-readable storage medium, storing computer programs thereon. Thecomputer programs, when executed by a processor, may perform stepsdescribed below. A downstream bandwidth allocation is performed. Aresult of the downstream bandwidth allocation is sent. Traffic data issent based on the result of the downstream bandwidth allocation. Where,the result of the downstream bandwidth allocation carries opticalnetwork unit (ONU) indication information.

When an OLT performs the downstream bandwidth allocation, the computerprograms, when executed by the processor, may further perform a stepdescribed below. The downstream bandwidth allocation is performed basedon a local traffic data queue.

When the downstream bandwidth allocation is performed based on the localtraffic data queue, the computer programs, when executed by theprocessor, may further perform steps described below. One or more localtraffic data queues are established, and a priority is configured foreach queue of the one or more local traffic data queues. Based on adownstream bandwidth scheduling algorithm, a downstream bandwidthoccupied by each queue of the one or more local traffic data queues isdetermined according to a data length and the priority of each queue ofthe one or more local traffic data queues, and the downstream bandwidthallocation is performed.

After the downstream bandwidth occupied by each queue of the one or morelocal traffic data queues is determined and the downstream bandwidthallocation is performed, the computer programs, when executed by theprocessor, may further perform a step described below. Downstreambandwidths belonging to a same ONU are configured to be consecutive.

When the result of the downstream bandwidth allocation is sent, thecomputer programs, when executed by the processor, may further perform astep described below. Downstream bandwidth allocation information iscarried in a downstream frame, where each downstream bandwidth entry inthe downstream bandwidth allocation information includes the ONUindication information and downstream bandwidth feature information.Alternatively, an indication message for the downstream bandwidthallocation is sent, where the indication message carries the ONUindication information.

An embodiment of the present disclosure further provides acomputer-readable storage medium, storing computer programs thereon. Thecomputer programs, when executed by a processor, may perform stepsdescribed below. A result of a downstream bandwidth allocation isreceived and parsed. Traffic data in a corresponding slot is receivedbased on ONU indication information in the result of downstreambandwidth allocation. The result of downstream bandwidth allocationcarries the optical network unit (ONU) indication information.

When the result of downstream bandwidth allocation is received andparsed, the computer programs, when executed by the processor, mayfurther perform steps described below. Each downstream bandwidth entryis acquired and parsed. And it is determined whether the ONU indicationinformation in a downstream bandwidth entry is consistent withidentification information of an ONU.

When the traffic data in the corresponding slot is received based on theresult of downstream bandwidth allocation, the computer programs, whenexecuted by the processor, may further perform a step described below.It is determined that the ONU indication information in the downstreambandwidth entry is consistent with the identification information of theONU, downstream bandwidth feature information in the downstreambandwidth entry is acquired, and the traffic data in the correspondingslot is obtained based on the downstream bandwidth feature information.

The embodiments of the present disclosure are described below inconjunction with scenario embodiments.

In some cases, an Ethernet passive optical network (EPON)/10 gigabitEthernet passive optical network (10 GEPON) ONU obtains a startingposition of an LLID by detecting a start of the LLID delimiter (SLD) of1 to 5 bytes in a preamble/start of frame delimiter (SFD), and obtainsthe LLID from 6 to 7 bytes, the ONU further needs to determine whetherthe LLID belongs to the ONU itself through 8-byte cyclic redundancycheck (CRC 8) check, and receives the corresponding Ethernet frame whenthe LLID belongs to the ONU itself, that is to say, even if a certainmedia access control (MAC) frame does not belong to this ONU, the ONUstill needs to detect the preamble/SFD, which causes a waste ofresources. Moreover, once a detection of a preamble/SFD field, forexample, the CRC 8 check fails, it is necessary to continue detectingthe preamble/SFD, and all detections before a next MAC frame are wasted.

A structure of a gigabit passive optical network (GPON)/10 gigabitpassive optical network (XG-PON) protocol superframe is composed of asuperframe head and a superframe payload. As shown in FIG. 8, in a GPON,the superframe includes a physical control block downstream (PCBd) and aGPON transmission convergence (GTC) payload. As shown in FIG. 10, in anXG-PON, the superframe includes an XG-PON transmission convergence(XGTC) header and an XGTC payload. The superframe payload is composed ofGPON encapsulation method (GEM) frames (as shown in FIG. 9) and XG-PONencapsulation method (XGEM) frames (as shown in FIG. 11). In FIG. 10,physical layer operations, administration and maintenance (PLOAM) isincluded. In FIG. 11, a burst is included.

In an embodiment of the present disclosure, an OLT on a sending side mayperform a downstream bandwidth allocation, obtain a result of thedownstream bandwidth allocation through a downstream bandwidthallocation algorithm, i.e., a dynamic bandwidth allocation (DBA)algorithm, and send downstream data according to the downstreambandwidth allocation; the OLT may send the result of the downstreambandwidth allocation to each ONU of one or more ONUs, and each ONU mayreceive corresponding downstream data according to the result of thedownstream bandwidth allocation and perform frame detection and dataprocessing.

First Alternative Embodiment

For a GPON system, in a downstream superframe, a downstream bandwidthmap (DS_BWmap) of the downstream bandwidth allocation may be carriedbefore a GPON encapsulation method (GEM) frame or a superframe payload.Each bandwidth entry in the DS_BWmap may include an ONU-ID, and startingtime and ending time in this superframe, as shown in FIG. 12.

The DS_BWmap is added into the GPON downstream superframe after anupstream bandwidth map (US_BWmap). Of course, a position of the DS_BWmapis only an exemplarily scheme of this embodiment, and the DS_BWmap maybe configured elsewhere. A definition of the US_BWmap is borrowed, andthe DS_BWmap may include 5 fields, as shown in FIG. 13.

ONU-ID: which identifies that a downstream bandwidth is allocated towhich ONU. Reserved: which is a reserved field. Start time (abbreviatedas STAT in FIG. 13): which represents the starting time of thedownstream bandwidth.

Stop time (abbreviated as STOT in FIG. 13): which identifies the endingtime of the downstream bandwidth. CRC: which represents CRC check bytes.

In addition, a PLend field may also be redefined. Original Blen isredefined as US_Blen, which represents a number of entries in theUS_BWmap, and original Alen is redefined as DS_Blen, which identifies anumber of entries in the DS_BWmap.

On the sending side:

One or more data queues may be established according to GEM Port-IDs,and a priority is configured for each queue of the one or more dataqueues. An OLT calculates a downstream bandwidth occupied by each queueof the one or more data queues in the superframe according to a datalength, the priority and the like of each queue of the one or more dataqueues by using a downstream bandwidth scheduling algorithm, andperforms an allocation. After the allocation is completed, appropriateadjustments may be performed. For example, bandwidths belonging to asame ONU are adjusted to be together, and then the DS_BWmap may beconstructed. GEM Port-ID bandwidths belonging to a same ONU and adjacentto each other may be configured as one bandwidth entry in the DS_BWmap.After the number of bandwidth entries in the DS_BWmap is counted, thenumber may be set in DS_Blen of the PLend field. The OLT may send thesuperframe carrying DS_Blen and DS_BWmap field to the ONU.

On the receiving side:

After acquiring the physical synchronization (PSync), the ONU mayacquire DS_Blen, and also acquire downstream bandwidth entries with anumber of DS_Blen after the US_BWmap, that is, the DS_BWmap. The ONU mayparse each downstream bandwidth entry, the CRC check may be performedfirst, when the CRC check is correct, it may be determined whether theONU-ID in a downstream bandwidth entry is the same as the ONU-ID of theONU itself, and when the ONU-ID is the same as the ONU-ID of the ONUitself, the start time and stop time may be acquired. Moreover, data inthe corresponding downstream bandwidth may be obtained by parsing acurrent superframe payload and then GEM frames may be parsed.

Second Alternative Embodiment

For an XG-PON1 system, in a downstream superframe, a downstreambandwidth map (DS_BWmap) of the downstream bandwidth allocation may becarried before an XGEM frame or a payload. Each bandwidth entry in theDS_BWmap may include an ONU-ID, and starting time and a bandwidth lengthin this superframe, as shown in FIG. 14.

The DS_BWmap may be added into the XG-PON1 downstream superframe after aUS_BWmap. Of course, a position of the DS_BWmap is only an exemplarilyscheme of this embodiment, and the DS_BWmap may be configured elsewhere.A definition of the US_BWmap is borrowed, and the DS_BWmap may include 5fields, as shown in FIG. 15.

ONU-ID: which identifies that a downstream bandwidth is allocated towhich ONU. Reserved: which is a reserved field. Start time (abbreviatedas STAT in FIG. 15): which represents the starting time of thedownstream bandwidth. Grant size (abbreviated as GRS in FIG. 15): whichidentifies a length of the downstream bandwidth. HEC: which representsHEC check bytes.

In addition, an HLend field may also be redefined. An original BWmaplength is redefined as a US_BWmap length, which represents a number ofentries in the US_BWmap, and a DS_BWmap length field is added after theUS_BWmap length and represents a number of entries in the DS_BWmap.

On the sending side:

One or more data queues may be established according to XGEM Port-IDs,and a priority is configured for each queue of the one or more dataqueues. An OLT calculates a bandwidth occupied by each queue of the oneor more data queues in the superframe according to the priority, a datalength and the like of each queue of the one or more data queues byusing the downstream bandwidth scheduling algorithm, and performs anallocation. After the allocation is completed, appropriate adjustmentsmay be performed. For example, bandwidths belonging to a same ONU areadjusted to be together, and the DS_BWmap may be constructed. XGEMPort-ID bandwidths belonging to a same ONU and adjacent to each othermay be configured as one bandwidth entry in the DS_BWmap. After thenumber of bandwidth entries in the DS_BWmap is counted, the number maybe set in the DS_BWmap length of the HLend field. The OLT may send thesuperframe carrying DS_BWmap length and DS_BWmap field to the ONU.

On the receiving side:

The ONU may acquire the DS_BWmap length, and also acquire downstreambandwidth entries with a number of DS_BWmap length after the US_BWmap,that is, the DS_BWmap. The ONU may parse each downstream bandwidthentry, an HEC check may be performed first, when the HEC check iscorrect, it may be determined whether the ONU-ID in a downstreambandwidth entry is the same as the ONU-ID of the ONU itself. When theONU-ID is the same as the ONU-ID of the ONU itself, the start time andgrant size may be acquired. Moreover, data in the correspondingdownstream bandwidth may be obtained by parsing a current superframeXGTC payload and then XGEM frames may be parsed.

Third Alternative Embodiment

This embodiment modifies the behaviors of the receiving side based onthe first alternative embodiment.

An ONU may acquire the DS_BWmap length, and also acquire downstreambandwidth entries with a number of the DS_BWmap length after theUS_BWmap, that is, the DS_BWmap. The ONU may parse each downstreambandwidth entry, the HEC check may be performed first, when the HECcheck is correct, it may be determined whether an ONU-ID in a downstreambandwidth entry is the same as the ONU-ID of the ONU itself. If theONU-ID is the same as the ONU-ID of the ONU itself, the ONU may acquirethe start time and stop time, and also acquire corresponding data byparsing a next superframe payload, and then GEM frames may be parsed.

Fourth Alternative Embodiment

This embodiment modifies the behaviors of the receiving side based onthe second alternative embodiment.

The ONU may acquire the DS_BWmap length, and also acquire downstreambandwidth entries with a number of the DS_BWmap length after theUS_BWmap, that is, the DS_BWmap. The ONU may parse each downstreambandwidth entry, the HEC check may be performed first, when the HECcheck is correct, it may be determined whether an ONU-ID in a downstreambandwidth entry is the same as the ONU-ID of the ONU itself. If theONU-ID is the same as the ONU-ID of the ONU itself, the ONU may acquirethe start time and grant size. Moreover, corresponding data may beobtained by parsing a next superframe XGTC payload and then XGEM framesmay be parsed.

Fifth Alternative Embodiment

In an EPON/10GEPON system, a DS_GATE message for the downstreambandwidth allocation may be sent, where the LLID in the preamble fieldmay indicate that a downstream bandwidth is allocated to which LLID.

As shown in FIG. 16, a structure of the message is similar to that ofGATE except that an Opcode field is modified as 0x0007, which indicatesthat the message is DS_GATE for allocating the downstream bandwidth. InFIG. 16, NG/F is short for a number of grants/Flags and represents anumber of allocated downstream bandwidths, GR #1 to GR #4 are short forGrant #1 to Grant #4 respectively, and respectively represent allocateddownstream bandwidth #1 to allocated downstream bandwidth #4. MSB andLSB are short for and represent a most significant bit and a leastsignificant bit respectively.

LLID: the LLID in the preamble/SFD field represents that this message isallocated to which LLID. Since the EPON/10GEPON ONU has only one LLID,it is equivalent to indicating that this message is allocated to whichONU.

Opcode: a value of this field is 0x0007, representing that the messageis DS_GATE for allocating the downstream bandwidth.

A group of the start time and the length represents one bandwidth entry,where the start time (abbreviated as STAT in FIG. 16) represents astarting time of a bandwidth entry, and the length represents a lengthof the bandwidth entry.

On the sending side:

One or more data queues may be established according to a virtual localarea network (VLAN) priority and the like, and a priority is configuredfor each queue of the one or more data queues. An OLT calculates abandwidth occupied by each queue of the one or more data queuesaccording to a data length, the priority and the like of each queue ofthe one or more data queues by using a downstream bandwidth schedulingalgorithm, and performs an allocation. After the allocation iscompleted, appropriate adjustments may be performed. For example,bandwidths belonging to a same ONU are adjusted to be together, and theDS_GATE may be constructed. Bandwidths belonging to a same ONU andadjacent to each other may be configured as one bandwidth entry in theDS_GATE. The OLT may send a superframe carrying the DS_GATE field to theONU.

On the receiving side:

The ONU may acquire the DS_GATE, and perform LLID detection and the CRCcheck. When the CRC check is correct, the ONU may determine whether theLLID in the DS_GATE is the same as the LLID of the ONU itself. When theLLID is the same as the LLID of the ONU itself, the ONU may parse eachdownstream bandwidth entry to acquire the start time and length, thenobtain corresponding data in a subsequent corresponding slot, and mayparse EPON/10GEPON frames.

Sixth Alternative Embodiment

An embodiment of the present disclosure reuses GATE. For a nextgeneration EPON (NGEPON), the PLID represents an ONU, and a PLID fieldis added into a bandwidth entry in GATE.

In an NGEPON system, the DS_GATE message for the downstream bandwidthallocation may be sent, where the preamble field carries a broadcastPLID, and the LLID (PLID) in the DS_GATE may indicate this bandwidth isallocated to which ONU.

As shown in FIG. 17, a structure of the message is similar to that ofGATE except that the Opcode field is modified as 0x0012, representingthat the message is DS_GATE for allocating the downstream bandwidth. InFIG. 17, GR is short for grant.

PLID: the PLID in the bandwidth entry represents the message isallocated to which ONU.

Opcode: the value of this field is 0x0012, representing that the messageis DS_GATE for allocating the downstream bandwidth.

A group of the start time and length represents one bandwidth entry,where the start time (abbreviated as STAT in FIG. 17) represents astarting time of a bandwidth entry, and the length represents a lengthof the bandwidth entry.

On the sending side:

One or more data queues may be established according to a VLAN priorityand the like, and a priority is configured for each queue of the one ormore data queues. An OLT calculates a bandwidth occupied by each queueof the one or more data queues according to a data length, the priorityand the like of each queue of the one or more data queues by using adownstream bandwidth scheduling algorithm, and performs an allocation.After the allocation is completed, appropriate adjustments may beperformed. For example, bandwidths belonging to a same ONU are adjustedto be together, and DS_GATE may be constructed. Bandwidths belonging toa same ONU and adjacent to each other may be configured as one bandwidthentry in DS_GATE. The OLT may send a superframe of the DS_GATE field tothe ONU.

On the receiving side:

The ONU may acquire the DS_GATE, and perform broadcast PLID detectionand the CRC check. When the broadcast PLID is determined, the ONU maycontinue to parse bandwidth entries in the DS_GATE, and determinewhether the PLID in a bandwidth entry is the same as the PLID of the ONUitself. When the PLID in the bandwidth entry is the same as the PLID ofthe ONU itself, the ONU may parse the corresponding downstream bandwidthentry to acquire the start time and length, obtain corresponding data ina subsequent corresponding slot, and may parse NGEPON frames.

An embodiment of the present disclosure further provides acomputer-readable storage medium, which is configured to storecomputer-executable instructions which, when executed, implement thedownstream bandwidth transmission method for a passive optical networkdescribed above.

Through the downstream bandwidth transmission method and apparatus for apassive optical network according to the embodiments of the presentdisclosure, the downstream bandwidth allocation is performed, the resultof the downstream bandwidth allocation is sent, and the traffic data issent based on the result of the downstream bandwidth allocation, wherethe result of the downstream bandwidth allocation carries the opticalnetwork unit (ONU) indication information. In the embodiments of thepresent disclosure, the downstream bandwidth is allocated to the ONU,and the corresponding ONU indication information is sent; and afterparsing the result of downstream bandwidth allocation, the ONU receivesthe downstream traffic data within the corresponding downstreambandwidth, the unnecessary parsing and determination behaviors areavoided, thereby improving the system efficiency, reducing the energyconsumption, and simplifying the system implementation complexity. Inaddition, wrong parsing of a certain frame header can be effectivelyprevented to parse subsequent data frames, and system reliability isimproved.

It will be understood by those skilled in the art that the embodimentsof the present disclosure may be provided as methods, systems orcomputer program products. Therefore, the present disclosure may adopt ahardware embodiment, a software embodiment, or a combination of hardwareand software embodiments. In addition, the present disclosure may adoptthe form of a computer program product implemented on one or morecomputer-usable storage media (including, but not limited to, a diskmemory, an optical memory, etc.) that include computer-usable programcodes.

The present disclosure is described with reference to flowcharts and/orblock diagrams of methods, devices (systems) and computer programproducts according to the embodiments of the present disclosure. It canbe understood that computer program instructions may be used forimplementing each flow in the flowcharts and/or each block in the blockdiagrams, and a combination of flows in the flowcharts and/or acombination of blocks in the block diagrams. These computer programinstructions may be provided for a processor of a general-purposecomputer, a special-purpose computer, an embedded processor or anotherprogrammable data processing device to produce a machine, so thatinstructions, which are executed via the processor of the computer oranother programmable data processing device, produce a means forimplementing functions specified in one flow in the flowcharts, one ormore blocks in the block diagrams, or at least one flow in theflowcharts and at least one block in the block diagrams.

These computer program instructions can also be stored in acomputer-readable memory which can direct the computer or anotherprogrammable data processing device to operate in a particular manner,so that the instructions stored in the computer-readable memory producea manufactured product including an instruction means. The instructionmeans implements the functions specified in one flow in the flowcharts,one or more blocks in the block diagrams, or at least one flow in theflowcharts and at least one block in the block diagrams.

These computer program instructions may also be loaded onto the computeror another programmable data processing device, so that a series ofoperations and steps are performed on the computer or anotherprogrammable device to produce processing implemented by the computer.Therefore, instructions executed on the computer or another programmabledevice provide steps for implementing the functions specified in oneflow in the flowcharts, one or more blocks in the block diagrams, or atleast one flow in the flowcharts and at least one block in the blockdiagrams.

It will be understood by those skilled in the art that functionalmodules/units in all or part of the steps of the methods, the systemsand the apparatuses disclosed above may be implemented as software,firmware, hardware and appropriate combinations thereof. In the hardwareimplementation, the division of the functional modules/units mentionedin the above description may not correspond to the division of physicalcomponents. For example, one physical component may have severalfunctions, or one function or step may be performed jointly by severalphysical components. Some or all components may be implemented assoftware executed by processors such as digital signal processors ormicrocontrollers, hardware, or integrated circuits such as applicationintegrated circuits. Such software may be distributed on acomputer-readable medium, which may include a computer storage medium(or a non-transitory medium) and a communication medium (or a transitorymedium). As is known to those skilled in the art, the term, computerstorage medium, includes volatile and nonvolatile, removable andnon-removable media implemented in any method or technology for storinginformation (such as computer-readable instructions, data structures,program modules or other data). The computer storage medium includes,but is not limited to, a random access memory (RAM), a read-only memory(ROM), an electrically erasable programmable read-only memory (EEPROM),a flash memory, or other memory technologies, a compact disc read-onlymemory (CD-ROM), a digital versatile disc (DVD) or other optical discstorage, a magnetic cassette, a magnetic tape, disk storage or othermagnetic storage apparatuses, or any other medium used for storingdesired information and accessible by a computer. In addition, as isknown to those skilled in the art, the communication medium generallyincludes computer-readable instructions, data structures, programmodules or other data in modulated data signals such as carriers orother transmission mechanisms, and may include any information deliverymedium.

It will be understood by those skilled in the art that modifications orequivalent substitutions may be made to the technical schemes of thepresent disclosure without departing from the spirit and the scope ofthe technical schemes of the present disclosure, and such modificationsand equivalent substitutions should fall within the scope of the claimsof the present disclosure.

What is claimed is:
 1. A downstream bandwidth transmission method for a passive optical network, comprising: performing, by an optical line terminal (OLT), a downstream bandwidth allocation; sending, by the OLT, a result of the downstream bandwidth allocation to a plurality of optical network units (ONUs); and sending, by the OLT, traffic data to the plurality of ONUs based on the result of the downstream bandwidth allocation, such that each of the plurality of ONUs only receives respective traffic data within a downstream bandwidth allocated to the respective ONU; wherein the result of the downstream bandwidth allocation sent by the OLT carries ONU indication information.
 2. The method of claim 1, wherein performing, by the OLT, the downstream bandwidth allocation comprises: performing, by the OLT, the downstream bandwidth allocation based on a local traffic data queue.
 3. The method of claim 2, wherein performing the downstream bandwidth allocation based on the local traffic data queue comprises: establishing at least one of local traffic data queues, and configuring a priority for each queue of the at least one of local traffic data queues; and determining, based on a downstream bandwidth scheduling algorithm, a downstream bandwidth occupied by each queue of the at least one of local traffic data queues according to a data length and the priority of each queue of the at least one of local traffic data queues, and performing the downstream bandwidth allocation.
 4. A downstream bandwidth transmission apparatus for a passive optical network, comprising a processor and a memory configured to store computer programs executable on the processor; wherein the processor is configured to: when executing the computer programs, perform the method of claim
 2. 5. The method of claim 3, wherein after determining the downstream bandwidth occupied by each of the at least one of local traffic data queues and performing the downstream bandwidth allocation, the method further comprises: configuring downstream bandwidths belonging to a same ONU to be consecutive.
 6. A downstream bandwidth transmission apparatus for a passive optical network, comprising a processor and a memory configured to store computer programs executable on the processor; wherein the processor is configured to: when executing the computer programs, perform the method of claim
 5. 7. A downstream bandwidth transmission apparatus for a passive optical network, comprising a processor and a memory configured to store computer programs executable on the processor; wherein the processor is configured to: when executing the computer programs, perform the method of claim
 3. 8. The method of claim 1, wherein sending the result of the downstream bandwidth allocation to the plurality of ONUs comprises: carrying downstream bandwidth allocation information in a downstream frame, wherein each downstream bandwidth entry in the downstream bandwidth allocation information comprises the ONU indication information and downstream bandwidth feature information; or sending an indication message of the downstream bandwidth allocation, wherein the indication message carries the ONU indication information.
 9. A downstream bandwidth transmission apparatus for a passive optical network, comprising a processor and a memory configured to store computer programs executable on the processor; wherein the processor is configured to: when executing the computer programs, perform the method of claim
 1. 10. A downstream bandwidth transmission method for a passive optical network, comprising: receiving and parsing, by an optical network unit (ONU), a result of a downstream bandwidth allocation; determining, by the ONU, downstream bandwidth feature information corresponding to the ONU according to the result of the downstream bandwidth allocation; and receiving, by the ONU, traffic data for the ONU according to the downstream bandwidth feature information; wherein the result of the downstream bandwidth allocation carries the ONU indication information.
 11. The method of claim 10, wherein receiving and parsing the result of the downstream bandwidth allocation comprises: acquiring and parsing each downstream bandwidth entry; and determining whether the ONU indication information in a downstream bandwidth entry is consistent with identification information of the ONU.
 12. The method of claim 11, wherein determining, by the ONU, the downstream bandwidth feature information corresponding to the ONU according to the result of the downstream bandwidth allocation, and receiving the traffic data for the ONU according to the downstream bandwidth feature information comprise: in response to determining that the ONU indication information in the downstream bandwidth entry is consistent with the identification information of the ONU, acquiring downstream bandwidth feature information in the downstream bandwidth entry as the downstream bandwidth feature information corresponding to the ONU, and obtaining the traffic data for the ONU according to the downstream bandwidth feature information corresponding to the ONU; and in response to determining that the ONU indication information in the downstream bandwidth entry is inconsistent with the identification information of the ONU, not acquiring the downstream bandwidth feature information in the downstream bandwidth entry, and not obtaining traffic data corresponding to the downstream bandwidth feature information in the downstream bandwidth entry.
 13. A downstream bandwidth transmission apparatus for a passive optical network, wherein the apparatus is applied for the downstream bandwidth transmission method for the passive optical network of claim 6 and configured in an optical network unit (ONU), comprising: a first receiving module, which is configured to receive and parse a result of a downstream bandwidth allocation, and determine downstream bandwidth feature information corresponding to the ONU according to the result of the downstream bandwidth allocation; and a second receiving module, which is configured to receive traffic data for the ONU according to the downstream bandwidth feature information; wherein the result of the downstream bandwidth allocation carries the ONU indication information.
 14. The apparatus of claim 13, wherein the first receiving module comprises: a parsing unit, which is configured to acquire and parse each downstream bandwidth entry; and a determination unit, which is configured to determine whether the ONU indication information in a downstream bandwidth entry is consistent with identification information of an ONU.
 15. A downstream bandwidth transmission apparatus for a passive optical network, comprising a processor and a memory configured to store computer programs executable on the processor; wherein the processor is configured to: when executing the computer programs, perform the method of claim
 10. 16. A downstream bandwidth allocation method for a passive optical network, comprising: performing, by an optical line terminal (OLT), a downstream bandwidth allocation, sending a result of the downstream bandwidth allocation to a plurality of optical network units (ONUs), and sending traffic data to the plurality of ONUs based on the result of the downstream bandwidth allocation, such that each of the plurality of ONUs only receives respective traffic data within a downstream bandwidth allocated to the respective ONU; and receiving and parsing, by one ONU of the plurality of ONUs, the result of the downstream bandwidth allocation, determining, by the one ONU, downstream bandwidth feature information corresponding to the ONU according to the result of the downstream bandwidth allocation; and receiving traffic data for the one ONU according to the downstream bandwidth feature information; wherein the result of the downstream bandwidth allocation carries the ONU indication information.
 17. A downstream bandwidth transmission apparatus for a passive optical network, wherein the apparatus is applied for the downstream bandwidth transmission method for the passive optical network of claim 1 and configured in an optical line terminal (OLT), comprising: an allocation module, which is configured to perform a downstream bandwidth allocation; and a sending module, which is configured to send a result of the downstream bandwidth allocation to a plurality of optical network units (ONUs) and send traffic data to the plurality of ONUs based on the result of the downstream bandwidth allocation, such that each of the plurality of ONUs only receives respective traffic data within a downstream bandwidth allocated to the respective ONU; wherein the result of the downstream bandwidth allocation carries ONU indication information.
 18. The apparatus of claim 17, wherein the allocation module comprises: a configuration unit, which is configured to establish at least one of local traffic data queues, and configure a priority for each queue of the at least one of local traffic data queues; and a processing unit, which is configured to: based on a downstream bandwidth scheduling algorithm and according to a data length and the priority of each queue of the at least one of local traffic data queues, determine a downstream bandwidth occupied by each queue of the at least one of local traffic data queues and perform the downstream bandwidth allocation.
 19. The apparatus of claim 17, wherein the sending module comprises: a first sending unit, which is configured to carry downstream bandwidth allocation information in a downstream frame, wherein each downstream bandwidth entry in the downstream bandwidth allocation information comprises the ONU indication information and downstream bandwidth feature information; or a second sending unit, which is configured to send an indication message of the downstream bandwidth allocation, wherein the indication message carries the ONU indication information.
 20. The apparatus of claim 17, wherein the allocation module is further configured to configure downstream bandwidths belonging to a same ONU to be consecutive. 